Author/Editor		Vrhovec, Sonja
Title		Vpliv membransko aktivnih učinkovin na vesikulacijo eritrocitov
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		1990
Volume		str. 91
Language		slo
Abstract		Mechanism of red blood cell vesiculation was studied where vesiculation was induced by physico chemical causes: decrease of pH, addition of ures, or increase of temperature. Human blood was used and its plasma replaced by other external solutions. At vesiculation induced by the decrease of pH the intermediate shapes were not the same as in cases of either added urea or increased temperature. Howeverm the final red blood cell shapes were in all three cases the same: cells became spherocytic and released vesicles with the membrane oriented as it is in a normal cell. Furher studies of vesiculation were performed in the presence of membrane active substances which are known to cause red blood cells to transform into either echinocytes or stomatocytes. Cells of these shapes were then used at initiation of all three vesiculation procedures employed. It was found that the stomatocytic agents agents chlorpromazine and aquinine prevent vasiculation in all three treated cases whereas echinocytic agents Na-salicylate and barbital had no effect. These results were interpreted on the basis of the bilayer couple model of red blood cell shape transformations and known interactions between the membrane active substances and the red blood cell membrane. Thus the observations were related to the area changes of the layers composing the membrane due to the employed physico chemical causes of vesiculation and due to the presence of the membrane active substances. Here it was taken into account that the decrease of pH causes aggregation of spectrin and that the urea and increased temperature cause spectrin denaturation and consequently also its aggregation. Therefore in all three treated cases the cytoskeleton is contracted and thus the area of the inner membrane layer is decreased which in view of the bilayer couple model leads to membrane evagination and the release of vesicles.(trunc.)
Descriptors		ERYTHROCYTES ERYTHROCYTE MEMBRANE HYDROGEN-ION CONCENTRATION UREA TEMPERATURE CHLORPROMAZINE QUININE SODIUM SALICYLATE BARBITAL